Blade for pug mills



H. R. STRAIGHT. BLADE FOR PUG MILLS- APPLICATION FILED JUNE 9. 1920.

' Pasfented De c. 12 ,'1922 Patented ll ec. 12, E922.

HALVEE R. STRAIGHT, 0F ADEL, IOWA.

BLADE FOB PUG IMILLS.

Application filed June 9,

To all whom it may concern:

Be it known that I, HALvnR R. Srnnisi-rr, a citizen of theUnited States, residing at Adel, in the county of Dallas, State of low-a, have invented a Blade for Pug Mills, of which the following is the specification.

This device relates to improvements in the blades for pug mills, and it is the object of my invention to provide an improved blade for pug mills, particularly, to increase its efiiciency and strength.

Pug mills are provided with either a horizontal or vertical shaft having a series of radial blades. A trough, or container, is provided to hold the material and a shaft is operatively mounted therein.

Fig. 1 is a transverse sectional view of a pug mill container and shaft showing my improved blades in position.

Fig. 2 is a plan and segmental view of the same.

In the accompanying drawing, I have shown one form of such a device, the container 10 is in the form of a trough and l have provided a shaft 11 rotatively mounted therein, the bearings are not shown as they form no part of my present invention.

The material to be pugged is fed into the top of the trough in a granular form and mixed with water. This mixing or pugging is best accomplished with a series of blades secured to the shaft when a certain amount of pressure is applied with the mixing. A. considerable amount of pressure is applied to the front edge of the blades as they are moved through the material and for this reason a considerable amount of trouble has been experienced in providing adequate means of securing the blades to the shaft.

My improved blade is formed of a comparatively thin piece of metal 12 having a shank 13 at one end and preferably to one side of the center line of blade so that a shoulder 14: is provided, the blade being considerably under the shank. I have also provided a rib, or flange, 15 at the inner end of the blade and it is curved to lit the shaft when the blade is in position.

1920. Serial E0. 387,764.

The shaft 11 is provided with a series of equal distant holes, or openings, 16 each of which is designed to receive a shank 13. The shanks are of such length as to pass about one half the way through the shaft and keyed in position by suitable keys 17. The blades are set at a slight angle to a transverse line with the shaft as shown in Fig. 1. The flanges 15 will rest against the shaft together with the shoulder 14-. By this arrangement it will be seen that a very rigid construction has been provided inas much as the backward pressure at the outer end of the blade causes a certairi amount of tensile strain on the shank instead of bendmg it.

When the shaft is rotated, at certain amount of end pressure will be exerted on'the material due to the action of the angular arrangement of the blade which causes the material to be moved towards one end. i I

This end is not sui'licient to give the desired )I'QSSUZG for proper mixing so I have provided a lateral flange 18 for each side of the blade 1 These flanges are formed circular and eccentrical with the center of the shaft so as to press the material toward the center of the shaft when said blades are rotated.

it will beseen as the shaft 11 is rotated and the material is fed to the container 10, it will be very thoroughly mixed with water and mixed to a very uniform and plastic material. The edge of the blade will separate and divide it while the flanges will press it together thereby producing a very uniform mixture.

Having thus described my invention, I claim:

blade for a pug mill consistingof a body portion and a shankQsaid body portion having curved side ribs on its end adjacent to the shankyand side ribs intermediate its ends, the latter named ribs being eccentric to the first named ribs. 7

2. A blade'for a pug mill, consisting of 'a body portion and a shank, said body por-' tion having curved side ribs on its end adacent to the shank, and slde ribs intermei a body portion and a shank said body portion having curved side ribs on its end adjacent to the shank, and side ribs eccentric to the first named ribs, the shank bemg intermediate to the front and rear edges of 10 the body portion.

4. A blade for a pug mill, consisting of a body portion and a shank, said body portion having curved side ribs on its end adjacent to the shank and said ribs being ecl5 centric to the first named ribs.

HALVERR. STRAIGHT. 

